Jackpot wagering systems are well known in land-based casinos. The most common such wagering system is found in a simple three-reel slot machine. Each reel of the slot machine has, say, 30 indexed positions, some or all of which may display a corresponding indicium. A player of the slot machine is required to place a wager by introducing coins, tokens or credit into the slot machine, which then enables each of the three reels to be spun and to come to rest ay any of the indexed positions. One resulting combination of indexed rest positions usually allows the player to win a prize consisting of a fixed jackpot. A slot machine with this particular geometry provides the player with a 1 in 27 000 chance of winning the fixed jackpot.
In order to take advantage of the random nature of the indexed rest positions of the reels, it is known to replace the fixed jackpot by a progressive jackpot in which a proportion of each wager placed by the player of the slot machine is used to increment the jackpot. The randomness makes it possible for the progressive jackpot to become large relative to the fixed jackpot described above, which enhances the attractiveness of the slot machine to would-be players thereof. It must, of course, be appreciated that the randomness also raises the possibility of the progressive jackpot being won when it is small relative to the above fixed jackpot.
The probability of winning the jackpot is the reciprocal of the number of all possible outcomes of the game that will, for convenience, be referred to as the jackpot cycle of the game. As an illustration, the jackpot cycle of the three-reel slot machine described earlier in this specification is 27 000. This means that, on average, 27 000 outcomes of the game must be determined in order for the contents of the progressive jackpot, to be won by the player.
The next step in the evolution of jackpot wagering systems was to link multiple slot machines having identical jackpot cycles to the same progressive jackpot, leading to the creation of larger and more attractive jackpots. Initially, the multiple identical slot machines linked to such progressive jackpots were clustered in close proximity to each other, such as within the confines of a land-based casino, but the advent of low-cost telecommunication networks soon enabled multiple remote clusters of identical slot machines to be linked to a single progressive jackpot. It is a characteristic of such distributed progressive jackpot wagering systems that they are restricted to casinos belonging to a single business enterprise.
The advent of open communication networks such as the Internet has led to a proliferation of online casinos, bringing online gaming within the reach of anyone with access to the World Wide Web of the Internet. Jackpot wagering systems and progressive jackpot wagering systems have now become available through such online casinos, Online progressive jackpot wagering systems have evolved further to a point where it is now known for players at competing online casinos to be able to play identical casino games linked to a common progressive jackpot, Access to these types of progressive jackpot wagering systems is provided through Jackpot portals on the World Wide Web.